I have successfully upgraded a HP Pavilion Split X2 (13-r010dx) to use a modern M.2 SATA SSD with the help of an adapter circuit board. The results were stellar and, even though the adapter does not mount inside the computer properly, I have no plans to put the original drive back in. It was a compromised solution of its era and times have moved on.
A little over ten years ago, flash-based solid state drives started edging towards price levels affordable to normal computer buyers. A few bargain basement devices were released, and they were terrible. I had two JMF602-based drives that lasted through their 90-day warranty periods but not much beyond that. The big breakthrough in affordable and durable performance is credited to the Intel X25-M, but the capacity was quite small. SSD performance is something that I had to experience to be converted to a fan, and it was hard to get non-converts to accept living with 80GB of capacity when we had become accustomed to hundreds of gigabytes.
The compromised solution was the SSD/HDD hybrid drive: there is a magnetic platter hard disk drive, but there is also a small piece of flash memory acting as a small solid-state drive cache. The advertising proclaimed that we would get the capacity of a HDD with all the performance of a SSD. I thought the concept was enticing, but never actually got one to try.
I’m glad I did not, if this computer’s stock WD5000M21K hybrid drive is representative of the breed. Its performance was absolutely terrible. Maybe modern workloads overwhelmed its meager 8GB of flash cache. Maybe years of use has worn out the flash and there was no caching anymore. Whatever the reason, its performance was no better than a HDD, definitely nowhere near the performance of a real solid state drive.
Now solid state drives with plenty of elbow room are quite affordable, giving old computers a new lease on life. The hinderance of oddball connectors like the SFF-8784 become just a speed bump with help of adapters, so we don’t need to put up with the compromises of SSD/HDD hybrid drives anymore.